RT Journal Article
SR Electronic
T1 Pure Correlates of Exploration and Exploitation in the Human Brain
JF bioRxiv
FD Cold Spring Harbor Laboratory Press
SP 103135
DO 10.1101/103135
A1 Blanchard, Tommy C
A1 Gershman, Samuel J
YR 2017
UL http://biorxiv.org/content/early/2017/01/25/103135.abstract
AB Balancing exploration and exploitation is a fundamental problem in reinforcement learning. Previous neuroimaging studies of the exploration-exploitation dilemma could not completely disentangle these two processes, making it difficult to unambiguously identify their neural signatures. We overcome this problem using a task in which subjects can either observe (pure exploration) or bet (pure exploitation). Insula and dorsal anterior cingulate cortex showed significantly greater activity on observe trials compared to bet trials, suggesting that these regions play a role in driving exploration. A model-based analysis of task performance suggested that subjects chose to observe until a critical evidence threshold was reached. We observed a neural signature of this evidence accumulation process in ventromedial prefrontal cortex. These findings support theories positing an important role for anterior cingulate cortex in exploration, while also providing a new perspective on the roles of insula and ventromedial prefrontal cortex.